Lightning strike cut airfield power after Britannia 757-200 passed decision height and landed heavily

Momentary failure of the runway lights just before touchdown at Girona, Spain on a night approach in "torrential" rain led to a heavy, nose-down landing of a Britannia Airways Boeing 757-200 and the crew's loss of control, according to the Spanish accident report.

Although the aircraft left the runway and broke up, all nine crew and 236 passengers initially survived the 14 September 1999 accident. Five days later, however, a passenger died of internal injuries undetected at the time.

The first approach was to runway 02, from which the crew carried out a go-around. Then, running short of fuel, they positioned for an instrument landing system (ILS) approach to runway 20 as the wind had backed. At decision height the captain had the runway lights in sight but, just before touchdown, lightning struck the local area supply and the lights failed for 11s until standby power cut in. After an initial heavy touchdown, the aircraft pitched nose-down at 7û/s. This second impact collapsed the nose gear and damaged the avionics bay and cockpit floor, causing almost total electrical failure and disrupting flight and power control. After the initial landing the power increased, but the Spanish accident investigation commission CIAIAC could not determine whether this was selected by the captain; the result of the impact on the captain's body or control run damage. Both the flight data recorder and cockpit voice recorder stopped recording immediately after the second touchdown.

The primary accident cause was "the destabilisation of the approach below decision height with loss of external visual references and automatic height callouts immediately before landing, resulting in touchdown with excessive descent rate in a nose-down attitude. The resulting displacement of the nose landing gear support structure caused disruption to aircraft systems that led to uncommanded forward thrust increase and other effects that severely aggravated the consequences of the initial event." A contributory factor was "shock or mental incapacitation on the pilot flying at the failure of the runway lights, which may have inhibited him from making a decision to go-around".

DAVID LEARMOUNT / LONDON

 

Source: Flight International